In the operation of motor or engine-powered transportation and/or work-producing machines, a power transmission component is typically used to convert rotary power of a given speed, torque, and direction to rotary power having a different speed, torque, and/or direction. For example, an engine output rotation may be geared down to reduce speed and increase torque. Similarly, a transmission may enable the operator to selectively reverse the power transmission output relative to the engine output direction, e.g., to provide both forward and reverse movement of the machine.
The modification of transmission characteristics is executed via the actuation and deactuation of one or more clutches or, less commonly, the meshing and unmeshing of toothed gears. The execution of the engagement of previously unengaged entities should be executed only when the rotational speeds of the entities are close enough to avoid damage to the transmission and jarring of the machine. In an automatic transmission, this task, often referred to as synchronization, is typically required in order to prevent shifts from completing while the two entities to be engaged are moving at substantially different rotational speeds.
For example, certain industrial and construction machines use a dual clutch planetary transmission to allow power upshifting and downshifting between gears, while retaining the high mechanical efficiency of a manual transmission and eliminating the typical inefficiency of an automatic transmission having a torque converter. However, to increase the durability and efficiency of the transmission, it is important to properly engage and disengage the various elements, both in terms of timing and force.
A synchronizer is a component used in a transmission to bring two rotating entities to a substantially similar rotational speed prior to full engagement. The force used to engage the synchronizer is referred to herein as a synchronizer profile. If the synchronizer engagement force is increased too rapidly, the shift will be hard, causing poor drivability and high component wear. Conversely, if the synchronizer engagement force is increased too slowly, the shift will lag, causing extensive clutch wear and poor machine response. While there have been attempts in the past to provide effective synchronizer profiles, the inventors have observed that there remains a need in the art for a system for actively controlling one or more transmission shift synchronizers to increase transmission durability and improve the user experience.
While the principles disclosed herein are directed at least in part to overcoming one or more existing disadvantages, noted or otherwise, it will be appreciated that the innovation herein is defined by the attached claims without to regard to whether and to what extent the specifically claimed embodiment overcomes one or more of the noted problems in the existing technology. Moreover, it will be appreciated that any discussion herein of any reference or publication is merely intended as an invitation to study the indicated reference itself, and is not intended to replace or supplement the actual reference. To the extent that the discussion of any reference herein is inconsistent with that reference, it will be appreciated that the reference itself is conclusive as to its teachings.